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Updated: Feb 20, 2026
A Microwave-Assisted Direct Heteroarylation of Ketones Using Transition Metal Catalysis
Published on: February 16, 2020
Cobalt-Catalyzed Asymmetric Sequential Hydroboration/Hydrogenation of Internal Alkynes
Jun Guo1, Biao Cheng1, Xuzhong Shen1
1Department of Chemistry, Zhejiang University , Hangzhou 310058, China.
Abstract:
A highly regio- and enantioselective cobalt-catalyzed hydroboration/hydrogenation of internal alkynes with HBpin and a hydrogen balloon in one pot was developed. A new type of chiral imidazoline iminopyridine (IIP) ligand was introduced for the first time in this novel and efficient strategy. This protocol used relatively simple and available starting materials with good functional group tolerance to construct more valuable chiral secondary organoboronates. The primary mechanistic studies illustrated that the cobalt-catalyzed regioselective hydroboration of alkynes did initially occur followed by HBpin-promoted and cobalt-catalyzed enantioselective hydrogenation of alkenylboronates.
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